Fibre reinforced film and method for the manufacturing thereof

ABSTRACT

Fibre reinforced film, characterised in that it is composed of a basalt fibre layer ( 2 ) which is provided on at least one side with a layer of thermoplastic material ( 3 ).

The present invention concerns an improved fibre reinforced film.

Glass fibre reinforced films which are composed of a layer of glassfibres provided on either side with a layer of polyethylene,polypropylene or any other thermoplastic whatsoever are generally known.

The problem which arises is that such glass fibre reinforced films areless appropriate for thermal recycling.

The melting point of the glass fibres is situated under the usualtemperature of a recycling oven, which has for a result that the glassfibres will melt during the thermal recycling and will adhere to theoven wall.

Moreover, it is known that glass fibres contain many harmful additiveswhich can be released during the thermal recycling.

The present invention aims to remedy the above-mentioned and otherdisadvantages.

To this end, the invention concerns a fibre reinforced film which iscomposed of a basalt fibre layer which is provided at least on one sidewith a layer of thermoplastic material.

A major advantage is that basalt is a natural product which can beprocessed into appropriate fibres without any additives.

Moreover, basalt has a melting point which is higher than theoperational temperature of a common recycling oven, such that, asopposed to for example glass fibres, the basalt fibres will not melt andadhere to the wall of the recycling oven in a harmful manner.

Consequently, basalt fibre reinforced films offer an appropriate answerto the need to use materials which can be recycled.

The recycleability and the absence of harmful additives is veryimportant, since such films are often applied in the interiors ofpassenger cars or lorries.

Moreover, compared to glass fibre reinforced films, basalt fibrereinforced films with a comparable bending stiffness are about 30% lessheavy.

The invention also concerns a method for manufacturing such basalt fibrereinforced films according to the invention.

This method consists in supplying a basalt fibre layer and in providinga layer of thermoplastic material on at least one side of the basaltfibre layer, after which the layer of thermoplastic material is pressedon and cooled.

In order to better explain the characteristics of the invention, thefollowing preferred embodiment of a basalt fibre reinforced film on theone hand and of a device with which the method according to theinvention for manufacturing a basalt fibre reinforced film can beapplied on the other hand, is given as an example only without beinglimitative in any way, with reference to the accompanying drawings, inwhich:

FIGS. 1 to 5 are sections representing different embodiments of animproved fibre reinforced film according to the invention;

FIG. 6 schematically represents a device which makes it possible to themethod according to the invention.

FIG. 1 represents a very simple embodiment of a fibre reinforced film 1according to the invention which mainly consists of a basalt fibre layer2 onto which is provided, on one side, a layer of thermoplastic material3, for example a layer of polyethylene or polypropylene.

The basalt fibre layer 2 in this embodiment consists of loose basaltfibres and is penetrated to a great extent by the thermoplasticmaterial.

The basalt fibres have for example a length of 8 to 10 mm and they havea sectional diameter of some 18 micrometer.

In FIG. 2, however, the layer 2 of basalt fibres is formed of a mat 4.

In this embodiment, the basalt fibre layer 2 is provided on both sideswith a layer of thermoplastic material 3, in this case made for exampleof polyethylene.

The basalt fibre layer 2 is penetrated by the thermoplastic material andboth layers of thermoplastic material 3 adhere through the openingsbetween the basalt fibres, such that together they form a matrixsurrounding the basalt fibres.

Such a film 1 is for example particularly appropriate for use ininterior applications of passenger cars and lorries. Such a film 1 isbest applied on a support which can be formed in a suitable mannertogether with the applied film.

FIG. 3 represents a basalt fibre reinforced film 1 which consists of abasalt fibre layer 2 provided on either side with a layer ofthermoplastic material 3, but in which perforations 5 have moreover beenprovided.

Such perforations 5 are particularly suitable to improve thesound-insulating qualities, which is particularly important for theapplication in vehicle interiors.

FIG. 4 represents a variant of the embodiment of a fibre reinforced film1 according to the invention, whereby a basalt fibre layer 2 is providedon either side with a layer of thermoplastic material 3, as in theembodiment represented in FIG. 2, and whereby moreover a membrane 6 orprotective layer is provided, and whereby a bonding layer 7 is providedon the other side of the film.

The membrane 6 forms a protection and/or decorative finish of the film1, whereas the bonding layer 7 is suitable for fixing the film 1 to asupport.

The membrane 6 may for example consist of polyester, polyester viscose,polyester cellulose or paper or the like.

The bonding layer 7 consists for example of ethylene vinyl acetate,ethylene acrylic acid, a co-polyester or a co-polyamide or the like.

FIG. 5 represents a special embodiment of a fibre reinforced film 1according to the invention which is more particularly formed of a basaltfibre layer 2, which is made here as a fabric on one side of which hasbeen provided a layer of thermoplastic material 3, for example a layerof polyethylene.

On top of this layer of polyethylene is provided a first bonding layer 8which is made for example of modified polyethylene, and on top of thelatter has been provided a barrier layer 9, for example made ofpolyamide.

On top of the barrier layer 9 is provided a second bonding layer 10 madeof polyethylene which is finally covered with a membrane 6 or coverlayer made of for example modified polyester.

The barrier layer 9 can be applied to prevent the binding material fromgoing through the film 1 during the process and/or in order to keep theback of the film 1 closed for acoustic reasons when the film 1 isapplied for example in car tops.

FIG. 6 schematically represents a device which makes it possible to themethod according to the invention.

The device as represented is based on a spool 11 onto which is provideda prefabricated basalt fibre mat 4.

Such a basalt fibre mat 4 can for example be made by solving basaltfibres in water and by providing this solution on a conveyor belt whichis provided with an underpressure at the bottom, such that the water isdrawn out of it, and whereby, during the drying process, a binder isadded, such that a paperlike layer is obtained.

Naturally, such a mat 4 can also be obtained in other ways, for exampleby mutually braiding the fibre threads, such that a fabric is obtained.

Downstream the device, as represented in FIG. 6, is provided a firstextrusion device 12 which provides a layer of thermoplastic material 3on the basalt fibre mat 4, for example polyethylene, and also a spool 13onto which is wound a polyester membrane 6 which is provided on top ofthe layer of thermoplastic material 3.

The whole is guided between a rubber pressure roller 14 and a metalcooling roller 15, such that the basalt fibre mat 4 is largelypenetrated by the polyethylene, and such that, simultaneously, thepolyester membrane 6 is laminated on the layer of thermoplastic material3.

The semi-finished film is subsequently turned around by means of returnpulleys 16 and carried with the non-processed side up to a second, inthis case double-working working extrusion device 17, and provided therewith a layer of thermoplastic material 3 and a bonding layer 7,according to what is called the co-extrusion technique.

The semi-finished film is guided in a similar manner as in the case ofthe first extrusion device 12 between a rubber pressure roller 13 and ametal cooling roller 15.

As a final processing, the thus obtained basalt fibre reinforced film 1is guided along a perforation cylinder 18 to be finally rolled up on aspool 19.

It is clear that this device merely illustrates the method whichconsists, in the most simple embodiment, in supplying a basalt fibrelayer 2 and in providing at least on one side of the basalt fibre layer2 a layer of thermoplastic material 3, after which the layer ofthermoplastic material 3 is pressed on and cooled.

The above-described device also makes it possible to subsequently alsoprovide a second layer of thermoplastic material 3, on the other side ofthe basalt fibre layer 2, and to press this layer 3 at least partly inthe basalt fibre layer 2 and cool it

The device also makes it possible to provide a membrane 6, together witha layer of thermoplastic material 3 which is being provided, by means ofco-lamination, or to simultaneously provide a bonding layer 7 by meansof co-extrusion.

It is clear that the layers of thermoplastic material 3 can also be bysimply adding agents to the basic material of the basic material to beextruded.

The present invention is by no means limited to the above-describedbasalt fibre reinforced films and the described method for manufacturingsuch films; on the contrary, such films according to the invention canbe made according to different variants while still remaining within thescope of the invention.

1. Fibre reinforced film, comprising a basalt fibre layer having on atleast one side thereof a layer of thermoplastic material.
 2. Fibrereinforced film according to claim 1, wherein the basalt fibre layerincludes on both sides a layer of thermoplastic material, each layeradhering to the other through openings between the basalt fibres, suchthat a matrix of thermoplastic material is created which comprises thebasalt fibres.
 3. Fibre reinforced film according to claim 1, includingperforations in the film.
 4. Fibre reinforced film according to claim 1,including a membrane on at least one side of the film.
 5. Fibrereinforced film according to claim 1, including a bonding layer on atleast one side of the film.
 6. Fibre reinforced film according to claim1, including a membrane on one side of the film and a bonding layer onthe other side of the film.
 7. Fiber reinforced film according to claim4, including a barrier layer between the layer of thermoplastic materialand the membrane.
 8. Fibre reinforced film according to claim 7,including a bonding layer between the layer of thermoplastic materialand the barrier layer.
 9. Fibre reinforced film according to claim 7,including a bonding layer between the barrier layer and the membrane.10. Fibre reinforced film according to claim 5, wherein the bondinglayer mainly comprises bonding material selected from the groupconsisting of ethylene vinyl acetate, ethylene acrylic acid,co-polyester and co-polyamide.
 11. Fibre reinforced film according toclaim 4, wherein the membrane comprises material selected from the groupconsisting of polyester viscose, polyester cellulose and paper. 12.Fibre reinforced film according to claim 1, wherein the layer ofthermoplastic material or the thermoplastic matrix is coloured. 13.Fibre reinforced film according to claim 1, wherein the basalt fibrelayer is made as a basalt fibre mat.
 14. Method for manufacturing abasalt fibre reinforced film comprising the steps: providing a basaltfiber layer; providing a layer of thermoplastic material on at least oneside of the basalt fibre layer; then pressing and cooling the layer ofthermoplastic material.
 15. Method according to claim 14, wherein, aftera layer of thermoplastic material has been provided on one side, andafter it has been pressed on and cooled, the basalt fibre layer with thelayer of thermoplastic material is turned, so that the provided layer ofthermoplastic material is disposed at or near the bottom, after which asecond layer of thermoplastic material is provided on the upwarddirected side of the basalt fibre layer, after which the second layer ofthermoplastic material is pressed on and cooled.
 16. Method according toclaim 14, wherein, together with a layer of thermoplastic materialprovided by means of extrusion, a membrane is with a layer ofthermoplastic material provided by means of extrusion, a membrane isapplied by means of co-lamination.
 17. Method according to claim 14,wherein, together with a layer of thermoplastic material being applied,a bonding layer is applied.
 18. Method according to claim 14, whereinafter one or several layers of thermoplastic material have been applied,and after they have been pressed on and cooled, and optionally aftereither or both a membrane and a bonding layer has been provided, thefilm is perforated.
 19. Method according to claim 14, including applyinga layer of thermoplastic material by means of extrusion or co-extrusion.